Although more particularly designed for an application in the automotive sector, the process according to the invention can also be used in all fields of economic activity in which there is occasion to produce panels having both protoberances and reinforcing elements.
At the present time, there are known different panels provided with reinforcing ribs formed from the mass.
However, in the such panels, the material of the ribs does not possess a density gradient permitting characteristics of compactness in the vicinity of their surfaces that are sufficient to ensure satisfactory absorption of external mechanical stresses and thus reinforce the panel efficiently.
Furthermore, in order to manufacture panels having protuberances and reinforcing elements, one has recourse to conventional processes in three successive stages. Firstly, there is moulded, for example, a support layer. Next, an independently formed outer piece forming a protuberance is then added on. Finally, the reinforcing elements are fixed to the panel.
However, such techniques have the drawback of involving multiple manufacturing operations. Indeed, in order to obtain the finished article, it is necessary to form the support layer, the protuberance and the reinforcing elements separately, to provide on each of them means to permit their cooperation and then to fix them to one another.
In addition, such processes consume a large amount of materials, which contributes to increasing their overall cost price.
The object of the present invention is to provide a process for the manufacture of a panel having at least one protuberance and reinforcing elements that makes it possible to remedy the aforementioned drawbacks by providing for their formation from the mass of the article.
A further object of the present invention is to provide a process, as well as a panel obtained through its implementation, integrating, in one and the same structure, several functionalities such as, for example, in the case of a vehicle door panel, the internal trim of the body, thanks to the panel itself, the comfort of the passengers thanks to the protuberances which form, for example, handles, and enhanced safety thanks to the integrated reinforcing elements.
A further object of the present invention is to provide a process for the manufacture of a panel having satisfactory shock absorpting properties, particularly in the case of localised impact.
Another object of the present invention is to provide a process for the manufacture of a panel the reinforcing elements of which are constituted by a surface compacted material.
Another object of the present invention is to provide a process for the manufacture of a panel having reinforcing elements distributed locally according to the stresses to which the panel is subjected when in use.
Furthermore, one advantage of the invention is to make it possible to reduce the quantity of material consumed in order to manufacture the panel, and thus limit its cost and weight.
A further advantage of the present invention is to facilitate recycling of the panel.
Further objects and advantages of the present invention will emerge in the course of the following description, which is given only by way of illustration and is not intended to limit same.